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      Chronotype, Social Jet Lag, and Cardiometabolic Risk Factors in Early Adolescence

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          Abstract

          Are chronotypes (evening vs morning preference) and social jet lag (sleep midpoint difference on weekends vs weekdays) associated with adiposity and cardiometabolic risk in young adolescents? This cross-sectional study found that evening chronotypes and greater social jet lag were associated with greater adiposity in adolescent girls, but not boys, independent of sleep duration. There were no associations with a cardiometabolic risk score. This study suggests that female adolescents may be more vulnerable to the obesogenic effects of circadian misalignment; obesity prevention efforts should consider regular sleep-wake patterns in addition to sleep extension and sleep quality improvement. Inadequate sleep duration and quality increase the risk of obesity. Sleep timing, while less studied, is important in adolescents because increasing evening preferences (chronotypes), early school start times, and irregular sleep schedules may cause circadian misalignment. To investigate associations of chronotype and social jet lag with adiposity and cardiometabolic risk in young adolescents. Starting in 1999, Project Viva recruited pregnant women from eastern Massachusetts. Mother-child in-person visits occurred throughout childhood. From January 23, 2012, to October 16, 2016, 804 adolescents aged 12 to 17 years completed 5 days or more of wrist actigraphy, questionnaires, and anthropometric measurements. A cross-sectional analysis using these data was conducted from April 31, 2018, to May 1, 2019. Chronotype, measured via a continuous scale with higher scores indicating greater evening preferences, and social jet lag, measured as the continuous difference in actigraphy sleep midpoint in hours from midnight on weekends vs weekdays, with higher values representing more delayed sleep timing on weekends. Adiposity, measured via anthropometry and dual-energy x-ray absorptiometry. For a subset of 479 adolescents with blood samples, cardiometabolic risk scores were computed as the mean of 5 sex- and cohort-specific z scores for waist circumference, systolic blood pressure, inversely scaled high-density lipoprotein cholesterol, and log-transformed triglycerides and homeostatic model of insulin resistance. Among the 804 adolescents in the study, 418 were girls and 386 were boys, with a mean (SD) age of 13.2 (0.9) years. In multivariable models adjusted for age, puberty, season, and sociodemographics, associations of chronotype and social jet lag with adiposity varied by sex. For girls, greater evening preference was associated with a 0.58-cm (95% CI, 0.12-1.03 cm; P  = .04 for interaction) higher waist circumference and 0.16 kg/m 2 (95% CI, 0.01-0.31 kg/m 2 ; P  = .03 for interaction) higher fat mass index as measured by dual-energy x-ray absorptiometry; each hour of social jet lag was associated with a 1.19-cm (95% CI, 0.04-2.35 cm; P  = .21 for interaction) higher waist circumference and 0.45 kg/m 2 (95% CI, 0.09-0.82 kg/m 2 ; P  = .01 for interaction) higher fat mass index as measured by dual-energy x-ray absorptiometry. Associations of social jet lag and evening chronotypes persisted for many measures of adiposity after adjustment for sleep duration and other lifestyle behaviors. By contrast, no associations were observed in boys. There were no associations with the cardiometabolic risk score for either sex, although statistical power was low for this outcome. Evening chronotypes and social jet lag were associated with greater adiposity in adolescent girls but not adolescent boys. Interventions aimed at improving sleep schedules may be useful for obesity prevention, especially in girls. This cross-sectional analysis of the Project Viva cohort investigates associations of chronotype and social jet lag with adiposity and cardiometabolic risk in young adolescents.

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          Most cited references22

          • Record: found
          • Abstract: found
          • Article: not found

          Validation of a self-administered instrument to assess stage of adolescent development.

          Drawings were made from Tanner's photographs illustrating five stages of development each for male genitalia, testicular size, male pubic hair, female breasts, and female pubic hair. Forty-seven females and forty-eight males aged 12-16 years indicated on questionnaires which stage they were most like, and answered other questions related to their physical development. Afterwards they were examined by physicians who had not seen their answers. Pearson correlation coefficients were 0.6 or above for the physician's observations compared with the adolescents' answers for the drawings, with the exception of testicular size. Answers to questions concerning amount of underarm hair and general development also yielded high correlations.
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            • Record: found
            • Abstract: not found
            • Article: not found

            Horne & Östberg morningness-eveningness questionnaire: A reduced scale

              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Sex difference in the near-24-hour intrinsic period of the human circadian timing system.

              The circadian rhythms of melatonin and body temperature are set to an earlier hour in women than in men, even when the women and men maintain nearly identical and consistent bedtimes and wake times. Moreover, women tend to wake up earlier than men and exhibit a greater preference for morning activities than men. Although the neurobiological mechanism underlying this sex difference in circadian alignment is unknown, multiple studies in nonhuman animals have demonstrated a sex difference in circadian period that could account for such a difference in circadian alignment between women and men. Whether a sex difference in intrinsic circadian period in humans underlies the difference in circadian alignment between men and women is unknown. We analyzed precise estimates of intrinsic circadian period collected from 157 individuals (52 women, 105 men; aged 18-74 y) studied in a month-long inpatient protocol designed to minimize confounding influences on circadian period estimation. Overall, the average intrinsic period of the melatonin and temperature rhythms in this population was very close to 24 h [24.15 ± 0.2 h (24 h 9 min ± 12 min)]. We further found that the intrinsic circadian period was significantly shorter in women [24.09 ± 0.2 h (24 h 5 min ± 12 min)] than in men [24.19 ± 0.2 h (24 h 11 min ± 12 min); P < 0.01] and that a significantly greater proportion of women have intrinsic circadian periods shorter than 24.0 h (35% vs. 14%; P < 0.01). The shorter average intrinsic circadian period observed in women may have implications for understanding sex differences in habitual sleep duration and insomnia prevalence.
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                Author and article information

                Journal
                JAMA Pediatrics
                JAMA Pediatr
                American Medical Association (AMA)
                2168-6203
                September 16 2019
                Affiliations
                [1 ]Division of Research, Kaiser Permanente Northern California, Oakland
                [2 ]Division of Chronic Disease Research Across the Lifecourse, Department of Population Medicine, Harvard Medical School, Harvard Pilgrim Health Care Institute, Boston, Massachusetts
                [3 ]Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, Massachusetts
                [4 ]Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts
                [5 ]Department of Neonatology, University of Tübingen, Tübingen, Germany
                [6 ]Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
                [7 ]Division of General Academic Pediatrics, Massachusetts General Hospital for Children, Boston
                Article
                10.1001/jamapediatrics.2019.3089
                6749538
                31524936
                06ed3b4d-6cba-4d4c-b61b-42481a28f715
                © 2019
                History

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